Alert archive / Arizona / Flash Flood Warnings in 2012

Flash Flood Warning 50, NWS Phoenix, AZ

August 21, 2012Maricopa County, Arizona

NWS Phoenix, AZ issued this flash flood warning at Aug 21, 2012, 8:28 PM MST for Maricopa County, Arizona. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 21, 2012, 8:28 PM MST (03:28 UTC)
Expired
Aug 21, 2012, 10:30 PM MST
In force
2 hr
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon
Flood severity
None

County Maricopa County, AZ

The radar

The Phoenix radar (KIWA), 90 km from the middle of the area, began a volume at 03:29 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Phoenix, AZ (KPSR), launched 00:00Z, 3.5 hours before the alert went out and 65 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Phoenix, AZ at 00:00Z on 2012-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 565 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phoenix, AZ at 00:00Z on 2012-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
565 J/kg
Mixed-layer CIN
-80 J/kg
Mixed-layer LCL
2143 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
30 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

246 
WGUS55 KPSR 220328
FFWPSR
AZC013-220530-
/O.NEW.KPSR.FF.W.0050.120822T0328Z-120822T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
828 PM MST TUE AUG 21 2012

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WEST CENTRAL MARICOPA COUNTY IN SOUTH CENTRAL ARIZONA...

* UNTIL 1030 PM MST

* AT 820 PM MST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
  NEARLY STATIONARY THUNDERSTORMS PRODUCING VERY HEAVY RAIN 
  THAT WILL CAUSE FLASH FLOODING. RADAR ESTIMATES UP TO ONE INCH
  HAS FALLEN IN THE LAST 20 MINUTES. 

* LOCATIONS IN THE WARNING INCLUDE STATE ROUTE 85 BETWEEN COTTON 
  CENTER AND BUCKEYE NEAR THE RAINBOW WASH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLOOD DEATHS OCCUR IN MOTORIZED VEHICLES. WHEN ENCOUNTERING
FLOODED ROADS...MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 3333 11268 3333 11253 3314 11258 3317 11273

$$

NOLTE
3 follow-up statements
443 
WGUS75 KPSR 220349
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
849 PM MST TUE AUG 21 2012

AZC013-220530-
/O.CON.KPSR.FF.W.0050.000000T0000Z-120822T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MARICOPA AZ-
849 PM MST TUE AUG 21 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1030 PM MST FOR WEST
CENTRAL MARICOPA COUNTY...

AT 843 PM MST...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED AN 
AREA OF THUNDERSTORMS PRODUCING VERY HEAVY RAIN THAT WILL CAUSE 
FLASH FLOODING. PRECIPITATION GAUGE LOCATED AT RAINBOW WASH NEAR
STATE ROUTE 85 HAS MEASURED OVER ONE AND ONE QUARTER INCHES OF RAIN
IN THE LAST THIRTY MINUTES. ADDITIONAL GAUGES IN THE AREA ARE REPORTING
UP TO ONE HALF INCH OF RAIN NEAR BUCKEYE AND GOODYEAR ON THE PERIPHERY
OF THE WARNING AREA. STORMS CONTINUE TO REMAIN STATIONARY OVER THE 
AREA...CONTINUING THE THREAT FOR FLASH FLOODING DUE TO HEAVY RAINFALL. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLOOD DEATHS OCCUR IN MOTORIZED VEHICLES. WHEN ENCOUNTERING
FLOODED ROADS...MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 3333 11268 3333 11253 3314 11258 3317 11273

$$

NOLTE
435 
WGUS75 KPSR 220413
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
913 PM MST TUE AUG 21 2012

AZC013-220530-
/O.CON.KPSR.FF.W.0050.000000T0000Z-120822T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MARICOPA AZ-
913 PM MST TUE AUG 21 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1030 PM MST FOR WEST
CENTRAL MARICOPA COUNTY...

AT 907 PM MST...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED TO
MONITOR AN AREA OF MOSTLY STATIONARY THUNDERSTORMS PRODUCING HEAVY
RAINFALL ACROSS PORTIONS OF WEST CENTRAL MARICOPA COUNTY. 

RAIN GAUGE AT RAINBOW WASH HAS MEASURED OVER ONE AND THREE QUARTER
INCHES OF PRECIPITATION OVER THE LAST HOUR. RAINBOW WASH IS REPORTED
TO BE RUNNING IMPACTING OLD US 80 AND POTENTIALLY STATE ROUTE 85 AS
WELL. RADAR INDICATES THUNDERSHOWERS CONTINUE ACROSS MUCH OF THE 
AREA...ALLOWING FOR ADDITIONAL RAINFALL ACCUMULATIONS ACROSS THE
WARNING AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOST FLOOD DEATHS OCCUR IN MOTORIZED VEHICLES. WHEN ENCOUNTERING
FLOODED ROADS...MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 3333 11268 3333 11253 3314 11258 3317 11273

$$

NOLTE
773 
WGUS75 KPSR 220527
FFSPSR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
1027 PM MST TUE AUG 21 2012

AZC013-220535-
/O.EXP.KPSR.FF.W.0050.000000T0000Z-120822T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MARICOPA AZ-
1027 PM MST TUE AUG 21 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 1030 PM MST FOR WEST
CENTRAL MARICOPA COUNTY...

RAINFALL ACROSS THE RAINBOW WASH DRAINAGE TOTALED BETWEEN ONE AND
THREE QUARTER INCHES TO OVER TWO INCHES ACROSS THE AREA THIS
EVENING. FLOW HAS BEEN REPORTED IN RAINBOW WASH AND IMPACTS 
ASSOCIATED WITH HEAVY RAINFALL WILL CONTINUE FOR THE NEXT FEW HOURS. 

AVOID DRIVING THROUGH WATER COVERED ROADWAYS...ESPECIALLY AT NIGHT.
REMEMBER...TURN AROUND DO NOT DROWN.

LAT...LON 3333 11268 3333 11253 3314 11258 3317 11273

$$

NOLTE

The office that day

Everything else NWS Phoenix, AZ issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 21, 5:10 PM MSTSpecial Weather StatementPSRLa Paz80 min
Aug 21, 5:29 PM MSTSpecial Weather StatementPSRPinal46 min
Aug 21, 5:37 PM MSTFlash Flood WarningPSRLa Paz83 min
Aug 21, 5:55 PM MSTSevere Thunderstorm WarningPSRLa Paz65 min
Aug 21, 5:59 PM MSTSpecial Weather StatementPSRMaricopa76 min
Aug 21, 6:00 PM MSTSevere Thunderstorm WarningPSRLa Paz39 min
Aug 21, 6:09 PM MSTSpecial Weather StatementPSRPinal51 min
Aug 21, 6:12 PM MSTFlash Flood WarningPSRLa Paz71 min
Aug 21, 6:51 PM MSTFlash Flood WarningPSRLa Paz75 min
Aug 21, 6:56 PM MSTAreal Flood AdvisoryPSRGila, Maricopa, Pinal3 hr
Aug 21, 6:57 PM MSTSevere Thunderstorm WarningPSRPinal33 min
Aug 21, 7:03 PM MSTBlowing Dust AdvisoryPSR57 min
Aug 21, 7:05 PM MSTFlash Flood WarningPSRPinal55 min
Aug 21, 7:09 PM MSTSpecial Weather StatementPSRLa Paz66 min
Aug 21, 7:30 PM MSTSevere Thunderstorm WarningPSRPinal30 min
Aug 21, 7:37 PM MSTSpecial Weather StatementPSRMaricopa53 min
Aug 21, 7:49 PM MSTAreal Flood AdvisoryPSRLa Paz90 min
Aug 21, 8:00 PM MSTFlash Flood WarningPSRPinal30 min
Aug 21, 8:16 PM MSTAreal Flood AdvisoryPSRMaricopa119 min
Aug 21, 9:02 PM MSTAreal Flood AdvisoryPSRMaricopa118 min
Aug 21, 9:32 PM MSTAreal Flood AdvisoryPSRMaricopa, Pinal118 min
Aug 21, 9:53 PM MSTSpecial Weather StatementPSR37 min
Aug 21, 10:07 PM MSTSpecial Weather StatementPSRYuma38 min
Aug 21, 10:24 PM MSTBlowing Dust AdvisoryPSR3 hr
Aug 21, 10:40 PM MSTAreal Flood AdvisoryPSRLa Paz81 min
Aug 21, 10:54 PM MSTSpecial Weather StatementPSR66 min
Aug 21, 11:15 PM MSTSpecial Weather StatementPSRLa Paz75 min
Aug 22, 1:34 PM MSTFlash Flood WatchPSR15 hr
Aug 22, 1:44 PM MSTFlash Flood WarningPSRMaricopa, Pinal3 hr
Aug 22, 2:32 PM MSTAreal Flood AdvisoryPSRMaricopa118 min

Nearby

Flash Flood Warnings in Arizona, 2012Every flash flood warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.